Resistance to important malaria medicaments in seriously ill children in Africa
Resistance to important malaria medicaments in seriously ill children in Africa
scientists have for the first time Artemisinin-Resistenz, ein wichtiges Malaria-Medikament, bei Kindern in Afrika mit schwerer Krankheit festgestellt. The continent is responsible for 95% of all malaria deaths worldwide, whereby children are most affected.
"If this is confirmed by other studies, this could change the guidelines for the treatment of severe malaria in African children who are by far the largest target group," says Chandy John, specialist for pediatric infectious diseases at Indiana University in Indianapolis. John is a co-author of the study, which published in Jama 1 today and today at the annual meeting of the American Society of Tropical Medicine and Hygiene was presented in New Orleans, Louisiana.
Before was Artemisinin resistance Detected in children in Africa, but the now specific identification in children with severe malaria increases the level of threat. The malaria pathogen, plasmodium falciparum, is transmitted by a mosquito bite. To treat "uncomplicated", not heavier, malaria recommends the World Health Organization Treatment with pills that contain an artemisin derivative that quickly eliminate most malaria parasites in the body, combined with a "partner" medication that circulates longer in the body and kills the remaining parasites. These treatment regimes are referred to as artemisinin -based combination therapies (acts).
Treatment of heavy malaria, which can include symptoms such as cramps, breathing problems and abnormal bleeding, requires more intensive measures. The doctors give intravenous artesunate-a fast-acting version of artemisinin-for at least 24 hours, followed by an act dose. A quick treatment of severe malaria is crucial for recovery, according to the researchers.
difficult to treat
The latest study in Jinja, Uganda, examined children aged 6 months to 12 years with severe malaria. The researchers found that 11 of the 100 participants, about 10%, had partial artemisinin resistance. This term refers to a delay in the elimination of the malaria parasites from the body after treatment; A partially resistant infection is classified as such in which the medication takes longer than 5 hours to kill half of the malaria parasites.
In the past, researchers have associated specific mutations in proteins from P. Falciparum to the appearance of partial artemisinin resistance 2 . This means that the parasites develop further to escape the "gold standard" malaria treatment. John and his colleagues analyzed the genomes of parasites that the children infected in their study and found that ten participants had one of two types of these mutations. One of the mutations that was found in eight participants was associated with a longer duration of artemisinin to eliminate the parasite.Another group of ten children in the study had a malaria infection that returned after completing their treatment. These cases were not due to the existence of known artemisinin-resistance mutations. John suspects that the return by a resistance to Lumefordrin could have been caused, a partner medication that is given orally in the act of treatment for severe malaria. However, further studies are required to evaluate this option, says John. "What the return suggests to us is that maybe the partner drug does not work as well as it should because the parasites come back," he adds.
Since the resistance to Artemisinin was first identified in Southeast Asia in the 2000s, the greatest concern of the scientists is how this will affect the treatment of serious malaria cases, says Philip Rosenthal, a malaria specialist at the University of California, San Francisco. "Even if the drug continues to work, the slower effect could make a difference and lead to higher death rates," he explains.
The study by John and his colleagues, however, does not offer a final answer to whether the artemisinin resistance already leads to poorer clinical results, Rosenthal notes. The study group was too small, and all analyzed children finally recovered, even if this process sometimes lasted longer than expected. This only shows that the current treatments for heavy malaria are not "quite as good as we might have hoped," he says.
However,Rosenthal and others are still concerned about this news. "The appearance of partial artemisinin resistance in Africa is a big threat to malaria control," he says. "We are now starting to understand what is going on."
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Henrici, R. C. et al. Jama https://doi.org/10.1001/jama.2024.22343 (2024).
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Rosenthal, P. J., Asua, V. & Conrad, M. D. Nature Rev. Microbiol. 22, 373–384 (2024).